This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2001-018691, filed Jan. 26, 2001, the entire contents of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to a method of forming an artificial Shiro of Tricholoma Matsutake (hereinafter referred to as xe2x80x9cMatsutakexe2x80x9d).
2. Description of the Related Art
Generally, as a method for efficiently cultivating a large amount of mushrooms, a method of proliferating mycelia of the mushroom in a liquid culture medium is known. However, in case of Matsutake mushrooms, their production requires a root of a living tree, because Matsutake is an ectomycorrhizal fungus. An assembly of hyphae called a xe2x80x9cShirowxe2x80x9d is present in the site where a Matsutake mushroom grows, and therefore induction of the Shiro formation is an important step toward increasing the production of Matsutake mushrooms (Makoto Ogawa, Biology of Matsutake, pp 333, published by Tsukiji Shokan).
However, in a natural environment, saprobe and sugar fungus preferentially proliferate in the nutrient site where a red pine (i.e., a host plant of a Matsutake fungus) grows. Because of this, it is difficult for a Matsutake fungus (a symbiotic fungus) to form its Shiro.
Various studies have been made on artificial cultivation of Matsutake mushrooms (Tricholoma Matsutake (S. Ito et Imai) Sing.) from long ago. Nevertheless, it is still impossible to cultivate Matsutake mushrooms artificially.
The results of studies that have been made on the artificial cultivation of Matsutake mushrooms will be described below.
Masui has experimentally showed that Matsutake forms a mycorrhizal association with a root of a red pine (Masui, K. (1927), Mem. Coll. Sci. Kyoto Univ. B (2) 2, 149-279). Tominaga has investigated the optimal conditions for growth of Matsutake hyphae (Tominaga, Y. (1965) Bull. Hiroshima Agri. Coll. 2: 242-246). Ogawa et al. have investigated the formation of a Matsutake fruit body primordium by axenic culture (Ogawa, M and Hamada, M (1975), Trans. Mycol. Soc. Japan 16: 406-415). However, success in the induction of Matsutake Shiro formation has not yet been reported.
To make the present invention, the present inventors have focused on the fact that the Matsutake hyphae grow extremely slowly. They considered that the slow growth of the hyphae might be one of the factors that hindered advancements of artificial cultivation of Matsutake mushrooms. Up to now, in an attempt to produce Matsutake mushrooms in a large amount, artificial formation of a new Shiro has been tried by inoculating Matsutake hyphae into a host plant-growing forest. However, by such a trial, Matsutake hyphae have not grown to form a Shiro to the extent of practical use. Therefore, it is presently considered difficult to cultivate Matsutake mushrooms artificially.
In view of the aforementioned background, the present inventors have made extensive studies on a method of inducing the formation of an artificial Shiro of Matsutake, which is an important step toward increasing the production of Matsutake mushrooms. Therefore, an object of the present invention is to provide a method capable of rapidly forming an artificial Shiro of Matsutake.
The present inventors found an active principle capable of promoting the growth of Matsutake hyphae. Based on this finding, they established a method of proliferating Matsutake hyphae in a short time, thereby accomplishing the present invention. More specifically, the present invention is achieved by the means described below.
(1) A method of forming an artificial Shiro of Matsutake comprising:
culturing Matsutake hyphae in a culture substrate containing a substance capable of controlling the cell membrane permeability of the hyphae as an active principle.
(2) A method of forming an artificial Shiro of Matsutake comprising:
culturing Matsutake hyphae in a culture substrate containing a substance capable of enhancing the hydrophilic property of the hyphae as an active principle.
(3) A method of forming an artificial Shiro of Matsutake comprising:
culturing Matsutake hyphae in a culture substrate containing a surfactant and/or a natural vegetable oil as an active principle.
(4) A method of forming an artificial Shiro of Matsutake comprising:
culturing Matsutake hyphae in a culture substrate containing a fatty acid ester as an active principle.
(5) A method of forming an artificial Shiro of Matsutake, comprising:
inducing growth of Matsutake hyphae by aseptically homogenizing a colony of Matsutake hyphae and aseptically culturing the obtained hyphae in a liquid nutrient medium;
preparing an inoculum of Matsutake hyphae by aseptically replacing the liquid nutrient medium containing the growth-induced Matsutake hyphae with a liquid nutrient medium containing no carbon source; and
culturing aseptically the inoculum of the Matsutake hyphae in a culture substrate containing a substance capable of controlling the cell membrane permeability of the hyphae as an active principle.
(6) A method of forming an artificial Shiro of Matsutake, comprising:
inducing growth of Matsutake hyphae by aseptically homogenizing a colony of Matsutake hyphae and aseptically culturing the obtained hyphae in a liquid nutrient medium;
preparing an inoculum of Matsutake hyphae by aseptically replacing the liquid nutrient medium containing the growth-induced Matsutake hyphae with a liquid nutrient medium containing no carbon source; and
culturing aseptically the inoculum of the Matsutake hyphae in a culture substrate containing a substance capable of enhancing the hydrophilic property of the hyphae as an active principle.
(7) A method of forming an artificial Shiro of Matsutake, comprising:
inducing growth of Matsutake hyphae by aseptically homogenizing a colony of Matsutake hyphae and aseptically culturing the obtained hyphae in a liquid nutrient medium;
preparing an inoculum of Matsutake hyphae by aseptically replacing the liquid nutrient medium containing the growth-induced Matsutake hyphae with a liquid nutrient medium containing no carbon source; and
culturing aseptically the inoculum of the Matsutake hyphae in a culture substrate containing a surfactant and/or a natural vegetable oil as an active principle.
(8) A method of forming an artificial Shiro of Matsutake, comprising:
inducing growth of Matsutake hyphae by aseptically homogenizing a colony of Matsutake hyphae and aseptically culturing the obtained hyphae in a liquid nutrient medium;
preparing an inoculum of Matsutake hyphae by aseptically replacing the liquid nutrient medium containing the growth-induced Matsutake hyphae with a liquid nutrient medium containing no carbon source; and
culturing aseptically the inoculum of the Matsutake hyphae in a culture substrate containing a fatty acid ester as an active principle.
(9) The method of forming an artificial Shiro of Matsutake according to any one of (1) to (8), wherein a solution containing the active principle at the concentration of 0.2 to 10 wt % is used as the active principle.
(10) The method of forming an artificial Shiro of Matsutake according to any one of (1) to (9), wherein a solution containing the active principle which is prepared using an organic solvent and distilled water is used as the active principle.
(11) The method of forming an artificial Shiro of Matsutake according to any one of (1) to (10), wherein either one of soil having a grain size of 3 mm or less and an artificial substrate having a grain size of 2 mm or less is used as the culture substrate.
(12) The method of forming an artificial Shiro of Matsutake according to any one of (1) to (11), wherein the active principle is added to the culture substrate in a state of a solution containing the active principle, and weight ratio of the solution containing the active principle to the total weight is 15 to 30 wt %.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.